1. Field of the Invention
In a crane boom having a plurality of extendible and retractable telescoping sections, considerable abrasion can occur between adjacent sections during reciprocable operation of the boom. Typically, bearing surfaces are provided between adjacent boom sections to minimize the abrasion between such sections and to assure proper alignment of the extended boom assembly.
2. Prior Art
Since the top and bottom plates of adjacent boom sections are weight bearing surfaces as well as abrasive surfaces permanently installed bearing plates or shoes are provided at respective opposite ends of each boom section to minimize wear and abrasion between adjacent boom sections at these critical loading points. This type of permanent installation has heretofore been employed with respect to the side shoes provided on respective side walls of adjacent boom sections. These side wall installations are particularly troublesome to replace and in certain instances can require the dismantling and rebuilding of the entire boom assembly in order to effect replacement of such side shoe assemblies. Such a permanent type installation is not deemed necessary in view of the fact that the side shoes are merely provided to align adjacent boom sections and to minimize abrasion between adjacent boom sections and are not critical weight bearing assemblies.
Accordingly, it would be desirable if the side shoe assemblies of a telescoping crane boom assembly could be made readily replaceable with minimum disassembly of the boom assembly.
Additionally, it would be desirably if such replacement side shoe assemblies would include an abradable member which is readily adjustable to compensate for wear caused by cyclic operation of the boom assembly.